Peter J, I have only driven the new Plus8 once, and with a Morgan salesman on board, the brown demo car, yours I think? I found the new Plus8 a lot firmer at the rear than the 5L.
The new Plus8 has linear springs and no progressive roll stiffness so its spring rates have to be stiffer than the 5L to control roll. We have gone for a soft initial spring rate for good ride then with the progressive springs and a geometry that stiffens in roll, I think that the 5L gives better ride. I have not driven the new Plus8 very hard, so at this stage unable to comment on that aspect.
The 5L also has as an option of very sophisticated dampers, of a type used on race cars, ie the single adjustable Quantums (will be spec'd for the front too). The new Plus8 has twin tube Spax I believe. Even the base level 5L will have monotube dampers with a separator piston which are more sophisticated than twin tube dampers. OK the new Plus8 could have decent dampers fitted of course, upgrades are always available.
I hope this helps - PJB.
